From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B226A369D4C; Wed, 20 May 2026 16:45:08 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779295509; cv=none; b=kIjT/WOkyzrzshGXNM9RG4DmVTtzZnf6GrzRkxAAQEDr5y01GbwBMLZgHjaNN5KJedB78z9J9xjy44sqZ93xIlrcCb/YpnWMCipNtj9/W9QlrAj43A4Tyu50YRAghatSvii71ZT+F3W0SjGg1AVRLxMmLbxeHFf2+lwjf8g3bcE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779295509; c=relaxed/simple; bh=Wl4llWjACVR2WMC6BcVC8h9Evee8mdVyKlvdv2wMUEo=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=ntNZHddtcnt+7S/mk/NgiA1RNxeYSWcDX4zsMX/4zGHBYFe4Fc0m82KEujs9WAjAC3159pKgbcaD4V4vAbfMGswtcDkebFgqhRl/F4amvZ/BpohDThb5JiqOmhN08QaSAM3mQRKqYgrK4mFA06Is+nyPF+n4fKmIfndCLiuhhHk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=KwoXKFFa; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="KwoXKFFa" Received: by smtp.kernel.org (Postfix) with ESMTPSA id DCCC41F000E9; Wed, 20 May 2026 16:45:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1779295508; bh=G8UQkiU0k+LK78dOgHrENAjXEpB/VAT5WFh62JFJsGw=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=KwoXKFFaces6vIFcq+cMjbRAoeqCwDFzo8CChSG2wr8h/8wKXz0hMQHKlhF0SxQCg SeFgfsIhLtvrYzLPuP/xZEpZ45+lgnesJpzWYC8oDIPJGU4dqlWUvWh5eyy19k7h9A qjxfEsnC62Oj6lCqfngzomS/sHPz6bGd7zQ+Zudk= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Thomas Zimmermann , Javier Martinez Canillas , Bart Van Assche , Sasha Levin , =?UTF-8?q?Christian=20K=C3=B6nig?= , Dmitry Baryshkov Subject: [PATCH 7.0 0429/1146] drm/fb-helper: Fix a locking bug in an error path Date: Wed, 20 May 2026 18:11:19 +0200 Message-ID: <20260520162157.898362793@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260520162148.390695140@linuxfoundation.org> References: <20260520162148.390695140@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 7.0-stable review patch. If anyone has any objections, please let me know. ------------------ From: Bart Van Assche [ Upstream commit bd64240dc88caaf7b96dd869f36f165f51b52039 ] The name of the function __drm_fb_helper_initial_config_and_unlock() and also the comment above that function make it clear that all code paths in this function should unlock fb_helper->lock before returning. Add a mutex_unlock() call in the only code path where it is missing. This has been detected by the Clang thread-safety analyzer. Cc: Thomas Zimmermann Cc: Christian König # radeon Cc: Dmitry Baryshkov # msm Cc: Javier Martinez Canillas Fixes: 63c971af4036 ("drm/fb-helper: Allocate and release fb_info in single place") Signed-off-by: Bart Van Assche Signed-off-by: Thomas Zimmermann Reviewed-by: Thomas Zimmermann Link: https://patch.msgid.link/20260403205355.1181984-1-bvanassche@acm.org Signed-off-by: Sasha Levin --- drivers/gpu/drm/drm_fb_helper.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c index 05803169bed57..16bfbfb0af161 100644 --- a/drivers/gpu/drm/drm_fb_helper.c +++ b/drivers/gpu/drm/drm_fb_helper.c @@ -1641,8 +1641,10 @@ __drm_fb_helper_initial_config_and_unlock(struct drm_fb_helper *fb_helper) drm_client_modeset_probe(&fb_helper->client, width, height); info = drm_fb_helper_alloc_info(fb_helper); - if (IS_ERR(info)) + if (IS_ERR(info)) { + mutex_unlock(&fb_helper->lock); return PTR_ERR(info); + } ret = drm_fb_helper_single_fb_probe(fb_helper); if (ret < 0) { -- 2.53.0